I tried using a bucket and a brown-glass growler to do my washing before pouring the yeast into the mason jars. Since neither the bucket nor the growler really let me see what I was doing, I was more or less just pouring blind. It looks like I ended up with a thin layer of yeast and a whole lot of trub.

Is it possible to salvage this, or should I just toss it and wait until I get some clear glass vessels to use?

Just pour off most of that beer leaving the yeast and trub and then follow the rest of the video.

Correction: you were already trying to wash it. With what you have there, just pour off the beer, add boiled and cooled wash water to fill it back up, and then wait 20 minutes for the trub to settle out. Then pour the yeast into clean containers.

The containers that you pour into don't necessarily need to be clear, but that would be nice.

You could just put all that in the fridge and wait until you get some clear containers.